diff --git a/pr_agent/settings/pr_description_prompts.toml b/pr_agent/settings/pr_description_prompts.toml
index 9c58eb3d..f85c9e7b 100644
--- a/pr_agent/settings/pr_description_prompts.toml
+++ b/pr_agent/settings/pr_description_prompts.toml
@@ -48,7 +48,7 @@ class FileDescription(BaseModel):
 class PRDescription(BaseModel):
     type: List[PRType] = Field(description="one or more types that describe the PR content. Return the label member value (e.g. 'Bug fix', not 'bug_fix')")
 {%- if enable_semantic_files_types %}
-    pr_files[List[FileDescription]] = Field(max_items=15, description="a list of the files in the PR, and their changes summary.")
+    pr_files: [List[FileDescription]] = Field(max_items=15, description="a list of the files in the PR, and their changes summary.")
 {%- endif %}
     description: str = Field(description="an informative and concise description of the PR. Use bullet points. Display first the most significant changes.")
     title: str = Field(description="an informative title for the PR, describing its main theme")